The patch titled mutex: add atomic_dec_and_mutex_lock has been removed from the -mm tree. Its filename was mutex-add-atomic_dec_and_mutex_lock.patch This patch was dropped because it was merged into mainline or a subsystem tree The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: mutex: add atomic_dec_and_mutex_lock From: Eric Paris <eparis@xxxxxxxxxx> Much like the atomic_dec_and_lock() function in which we take and hold a spin_lock if we drop the atomic to 0 this function takes and holds the mutex if we dec the atomic to 0. Signed-off-by: Eric Paris <eparis@xxxxxxxxxx> Signed-off-by: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> Cc: Paul Mackerras <paulus@xxxxxxxxx> Signed-off-by: Ingo Molnar <mingo@xxxxxxx> Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx> Cc: Christoph Hellwig <hch@xxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/mutex.h | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) diff -puN include/linux/mutex.h~mutex-add-atomic_dec_and_mutex_lock include/linux/mutex.h --- a/include/linux/mutex.h~mutex-add-atomic_dec_and_mutex_lock +++ a/include/linux/mutex.h @@ -151,4 +151,27 @@ extern int __must_check mutex_lock_killa extern int mutex_trylock(struct mutex *lock); extern void mutex_unlock(struct mutex *lock); +/** + * atomic_dec_and_mutex_lock - return holding mutex if we dec to 0 + * @cnt: the atomic which we are to dec + * @lock: the mutex to return holding if we dec to 0 + * + * return true and hold lock if we dec to 0, return false otherwise + */ +static inline int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock) +{ + /* dec if we can't possibly hit 0 */ + if (atomic_add_unless(cnt, -1, 1)) + return 0; + /* we might hit 0, so take the lock */ + mutex_lock(lock); + if (!atomic_dec_and_test(cnt)) { + /* when we actually did the dec, we didn't hit 0 */ + mutex_unlock(lock); + return 0; + } + /* we hit 0, and we hold the lock */ + return 1; +} + #endif _ Patches currently in -mm which might be from eparis@xxxxxxxxxx are linux-next.patch mutex-add-atomic_dec_and_mutex_lock-fix.patch fsnotify-unified-filesystem-notification-backend.patch fsnotify-add-marks-to-inodes-so-groups-can-interpret-how-to-handle-those-inodes.patch fsnotify-parent-event-notification.patch dnotify-reimplement-dnotify-using-fsnotify.patch fsnotify-generic-notification-queue-and-waitq.patch fsnotify-include-pathnames-with-entries-when-possible.patch fsnotify-add-correlations-between-events.patch fsnotify-allow-groups-to-add-private-data-to-events.patch fsnotify-fsnotify-marks-on-inodes-pin-them-in-core.patch fsnotify-handle-filesystem-unmounts-with-fsnotify-marks.patch inotify-reimplement-inotify-using-fsnotify.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html